US4044269A - Circuit arrangement for a repetition-blocking device - Google Patents

Circuit arrangement for a repetition-blocking device Download PDF

Info

Publication number
US4044269A
US4044269A US05/658,453 US65845376A US4044269A US 4044269 A US4044269 A US 4044269A US 65845376 A US65845376 A US 65845376A US 4044269 A US4044269 A US 4044269A
Authority
US
United States
Prior art keywords
circuit
switch
thyristor
threshold
transistor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US05/658,453
Other languages
English (en)
Inventor
Eduard Hermann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Application granted granted Critical
Publication of US4044269A publication Critical patent/US4044269A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B67—OPENING, CLOSING OR CLEANING BOTTLES, JARS OR SIMILAR CONTAINERS; LIQUID HANDLING
    • B67D—DISPENSING, DELIVERING OR TRANSFERRING LIQUIDS, NOT OTHERWISE PROVIDED FOR
    • B67D7/00—Apparatus or devices for transferring liquids from bulk storage containers or reservoirs into vehicles or into portable containers, e.g. for retail sale purposes
    • B67D7/06—Details or accessories
    • B67D7/08—Arrangements of devices for controlling, indicating, metering or registering quantity or price of liquid transferred
    • B67D7/22—Arrangements of indicators or registers
    • B67D7/221—Arrangements of indicators or registers using electrical or electro-mechanical means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B67—OPENING, CLOSING OR CLEANING BOTTLES, JARS OR SIMILAR CONTAINERS; LIQUID HANDLING
    • B67D—DISPENSING, DELIVERING OR TRANSFERRING LIQUIDS, NOT OTHERWISE PROVIDED FOR
    • B67D7/00—Apparatus or devices for transferring liquids from bulk storage containers or reservoirs into vehicles or into portable containers, e.g. for retail sale purposes
    • B67D7/06—Details or accessories
    • B67D7/32—Arrangements of safety or warning devices; Means for preventing unauthorised delivery of liquid
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/20—Modifications for resetting core switching units to a predetermined state

Definitions

  • the present invention relates to a circuit arrangement for a repetition-blocking device for preventing prohibited or undesired repetition of operations. This problem arises in a great number of technical fields. In chemistry, for example, it may be necessary during mixing processes not to permit the repeated addition of a given substance until another substance has been added.
  • Another field of application is the prevention of prohibited repetition of operations.
  • self-service filling pumps there may be cited self-service filling pumps.
  • misapplication is possible by illicitly reusing the filling pump after the first refueling operation and after the delivery of the voucher, unless this is prevented by automatic blocking devices.
  • a blocking circuit has been provided in self-service filling pumps, which is released upon replacement of the hose nozzle and can be unblocked again only by a special measure, e.g. by operating a switch at the cashier's desk.
  • a special control line from the control desk, which is located in the filling-station building and also contains the indicatorlamps, to the filling pump.
  • the fundamental idea of the invention is to use, in a manner known per se, one of the three phases for the control of the repetition-blocking device. According to the invention, however, the phase is not directly included in the control, but a control signal is derived indirectly, during the operation, by inserting into the respective phase conductor the primary winding or side of a transformer whose secondary side is connected to the control circuit.
  • the control circuit includes a threshold circuit to which, the secondary voltage of the transformer is applied, and which when an adjustable threshold voltage is exceeded -- this can be detected by means of a zener diode, for example, provides a signal to a memory circuit.
  • a switch, controlled by the threshold signal too, prevents any output from the memory circuit as long as the operation is going on.
  • the memory circuit After the memory circuit has been enabled, it provides a control signal to a controlled electronic switch inserted in the phase conductor, which signal changes this switch to the blocking state.
  • This blocking state can be unblocked, in known manner, only by a measure from the control desk.
  • the control line includes a circuit which prevents the threshold circuit from responding after the operation has been completed. This would be possible if, at the end of the first operation, a second operation were initiated before the switch inserted in the phase conductor is opened.
  • the circuit may be so designed that, during voucher printing, the secondary current does not suffice to restart the control circuit. In this case, it is sufficient to provide a delay circuit which causes the blocking signal not to reach the switch inserted in the phase conductor until the printing operation has been completed.
  • the invention has the advantage of eliminating the need for a special control line from the control center to the implement, e.g. to the filling pump. Another advantage lies in the fact that no high voltages are used in the control circuit. Furthermore, the control circuit can be realized in a very small space, and reliability is much better than in conventional control circuits.
  • FIG. 1 is a schematic diagram of the novel circuit arrangement
  • FIG. 2 shows an embodiment of the invention as a repetition-blocking device at a self-service filling pump.
  • FIG. 1 shows all parts of a repetition-blocking device which are essential to the invention; the repetition-blocking device is largely independent of the device to be blocked.
  • Designated by 1 is the load which can be connected to the power supply by means of a switch 2.
  • a controlled electronic alternating-current switch 3 Inserted in the phase conductor R, for example, is a controlled electronic alternating-current switch 3 and a transformer 4.
  • the switch 3 is closed in the initial state, On the secondary side of the transformer 4, a voltage is generated whose magnitude is dependent on the current flowing on the primary side, and which serves as the control voltage, as will be explained in the following.
  • the control voltage is applied through a closed switch 5 to a threshold circuit 6 which, when a predetermined voltage threshold is exceeded, provides a signal to a memory circuit 7.
  • the state of the memory circuit 7 thus indicates whether an operation is in progress or has been completed.
  • a bistable switch 8 is changed to its second state, and its output signal inhibits the memory circuit 7 from passing on the signal stored in it to the controlled electronic switch 3.
  • the operation i.e., when the switch 2 is opened, it must be insured that the switch 3 is opened and kept open until the memory circuit 7 is enabled again by an independent signal.
  • the switch 2 When the switch 2 is opened, the control voltage will drop below the threshold value, so the switch 8 will return to its initial state.
  • the inhibit signal is removed from the memory circuit 7, and the stored signal is fed as the control signal to the switch 3, which is opened. Thus, a repetition of the operation has been blocked.
  • the switch 5 may be provided, which is opened via the switch 8 when the operation has been finished. This will be explained in more detail below with the aid of FIG. 2.
  • the delay device 9 may be of advantage if blocking is not to be effected until after two operations, and if the delay time of the delay device 9 suffices to carry out the second operation. This is the case with self-service filling pumps, for example. After the hose nozzle has been replaced, whereby the fuel-pump motor is switched off, the voucher-printer motor is started. Only after the printing and delivery of the voucher must the filling pump be stopped. During this delay time, no new filling operation can be initiated as the switch 5 is open, whereby the repetition-blocking device becomes effective automatically. The repetition-blocking device can only be unblocked by a special signal which is sent from the control desk 10 to the switches 5 and 8, and to memory circuit 7, to return them to their initial state, so the switch 3 will be closed again.
  • FIG. 2 shows a detailed example of a circuit for a repetition-blocking device according to the invention for use with a self-service filling pump.
  • the control voltage is derived from the phase R.
  • the switch 11 is to indicate that it is possible to switch the load 1 between fuel pump and voucher printer.
  • the switch 3 (FIG. 1) is closed, and the indicator lamp 12 indicates that the filling pump is ready for operation.
  • the function of the switch 3 is performed by the triac Tr. This triac conducts, because the gate electrode is supplied with current through the resistors R11 and R14 which are connected to the output of rectifier bridge connected to the secondary side of the supply voltage transformer inserted in phase conductor R.
  • the thyristors Th1, Th2, and Th3 are cut off, because no control voltage is applied thereto.
  • the positive potential at the anode of Th1 then also prevails at the upper end of the resistor R3 and is retained when the control current decreases, and the current flowing through R3 is so high that the holding current of the thyristor Th1 is reached.
  • the resistor R1 and the capacitor C2 serve to divert undesired interference pulses.
  • the base of the transistor Th1 is driven into the conducting state, whereby the potential applied to the collector of this transistor through the resistor R5 becomes negative. Since, however, the transistor T2 must be driven with a positive potential, it is cut off. Thus, the signal stored by the thyristor Th1 cannot reach the thyristor Th2.
  • the load current decreases and the rectified secondary voltage of the transformer U1 drops below the breakdown voltage of the zener diode Z.
  • the transistor T1 is switched into the non-conducting state.
  • a positive potential is applied to the base of the transistor T2 through resistors R5 and R6, so that T2 will turn on.
  • the thyristor Th3 receives control current through the resistor R2, so that thyristors Th3 will turn on when a gate potential is applied thereto.
  • the load should be restarted immediately, voltage is prevented from reaching the thyristor Th1 via the zener diode Z, which then would be caused to conduct again.
  • the small load current of an indicator lamp which is always present, is sufficient.
  • the thyristor Th2 When the stored signal is applied from the thyristor Th1 to the gate electrode of the thyristor Th2, the latter is switched on. Thus, the potential between the resistors R11 and R14 becomes zero, and so does the control signal at the triac Tr, thus turning it off.
  • the thyristor Th2 can return to the blocking state only if the holding current is not sufficient to keep the thyristor conducting, i.e. when its anode potential becomes zero. This is accomplished by opening the push-button switch Ta for a short time, whereby the thyristors Th1 and Th2 return to the blocking state, too. Thus, the repetition-blocking device is again ready for operation.
  • the positive potential at the resistor R8 causes a current to flow through the resistors R9 and R10, so the capacitor C3 is charged with a time constant determined by resistors R9, R10, and C3.
  • the transistor T3 begins to conduct and transmits positive potential through the resistor R12 to the gate electrode of the thyristor Th2, so the latter is switched on and has zero potential at its anode, whereby the triac Tr is switched off.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Mathematical Physics (AREA)
  • Theoretical Computer Science (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
  • Electronic Switches (AREA)
US05/658,453 1975-02-24 1976-02-17 Circuit arrangement for a repetition-blocking device Expired - Lifetime US4044269A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE2507807A DE2507807C3 (de) 1975-02-24 1975-02-24 Schaltungsanordnung zum Verhindern der Wiederholung von Arbeitsvorgängen
DT2507807 1975-02-24

Publications (1)

Publication Number Publication Date
US4044269A true US4044269A (en) 1977-08-23

Family

ID=5939622

Family Applications (1)

Application Number Title Priority Date Filing Date
US05/658,453 Expired - Lifetime US4044269A (en) 1975-02-24 1976-02-17 Circuit arrangement for a repetition-blocking device

Country Status (4)

Country Link
US (1) US4044269A (en:Method)
AT (1) AT342702B (en:Method)
DE (1) DE2507807C3 (en:Method)
FR (1) FR2301969A1 (en:Method)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3033421A (en) * 1959-04-28 1962-05-08 William D Henderson Dispensing system
US3498501A (en) * 1968-03-01 1970-03-03 Tokheim Corp Dispensing control system
US3913069A (en) * 1974-10-21 1975-10-14 Autotank Ab Self service system
US3951307A (en) * 1973-07-11 1976-04-20 Kienzle Apparate Gmbh Timing of the control and resetting motor in a fuel dispensing arrangement

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3033421A (en) * 1959-04-28 1962-05-08 William D Henderson Dispensing system
US3498501A (en) * 1968-03-01 1970-03-03 Tokheim Corp Dispensing control system
US3951307A (en) * 1973-07-11 1976-04-20 Kienzle Apparate Gmbh Timing of the control and resetting motor in a fuel dispensing arrangement
US3913069A (en) * 1974-10-21 1975-10-14 Autotank Ab Self service system

Also Published As

Publication number Publication date
AT342702B (de) 1978-04-25
ATA79676A (de) 1977-08-15
FR2301969A1 (fr) 1976-09-17
DE2507807C3 (de) 1978-04-27
FR2301969B3 (en:Method) 1978-11-17
DE2507807B2 (de) 1977-08-18
DE2507807A1 (de) 1976-09-09

Similar Documents

Publication Publication Date Title
US4719553A (en) Inrush-current limiter for switching regulator power supply
US4937731A (en) Power supply with automatic input voltage doubling
US4150411A (en) Ground fault circuit interrupter utilizing a single transformer
US3573550A (en) Automatically resetting transient protection device
US4931893A (en) Loss of neutral or ground protection circuit
US3403318A (en) Static inverter system with frequency regulation of inverter output voltage as a function of inverter input voltage amplitude
US3377540A (en) Overload protection circuit for solid state power supplies
JPH0249001B2 (en:Method)
US5136175A (en) Current supply circuit arrangement
US3348118A (en) Battery charging circuits
US3643405A (en) Circuit arrangement for automatic control of the voltage of an electrical filter
US4382222A (en) Series regulated rectifier circuit for a battery charging system
US6373319B1 (en) Bistable high-voltage bidirectional switch
US4044269A (en) Circuit arrangement for a repetition-blocking device
US3708685A (en) High inductive load energizing circuit
JPS601808B2 (ja) 欠相検出方式
US3526812A (en) Power supply for circuit breaker tripping
GB1589663A (en) Power supply circuits
US3353082A (en) Fixed power supply utilizing a commutated rectifier
US3671807A (en) Control apparatus
US3714546A (en) Constant voltage transformers
US3654539A (en) Ac-dc converter
US3584262A (en) Solid-state on delay time delay apparatus
US4731550A (en) Circuit having a feed circuit for supplying current to a load resistor
US2914702A (en) Adjustable instantaneous overload trip device